全文获取类型
收费全文 | 282篇 |
免费 | 15篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 86篇 |
金属工艺 | 2篇 |
机械仪表 | 16篇 |
建筑科学 | 12篇 |
能源动力 | 11篇 |
轻工业 | 54篇 |
水利工程 | 2篇 |
无线电 | 27篇 |
一般工业技术 | 37篇 |
冶金工业 | 12篇 |
原子能技术 | 1篇 |
自动化技术 | 33篇 |
出版年
2024年 | 2篇 |
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 14篇 |
2020年 | 6篇 |
2019年 | 11篇 |
2018年 | 12篇 |
2017年 | 13篇 |
2016年 | 7篇 |
2015年 | 11篇 |
2014年 | 13篇 |
2013年 | 28篇 |
2012年 | 20篇 |
2011年 | 19篇 |
2010年 | 16篇 |
2009年 | 18篇 |
2008年 | 16篇 |
2007年 | 12篇 |
2006年 | 9篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有298条查询结果,搜索用时 15 毫秒
1.
2.
Irine Banu Lucy 《Journal of Materials Science》2007,42(14):5875-5879
Capacitance and dielectric loss measurements were carried out using an Al/Cu–GeO2/Al sandwich structure for 0 to 10 vol% Cu films, 120–400 nm thick, deposited at 0.4–1.5 nm/s in the frequency and temperature
range 1–106 Hz and 90–573 K, respectively. The variation of capacitance and dielectric loss with frequency and temperature follows the
Goswami and Goswami model. Capacitance decreases slowly with increasing thickness and also varies with the change in deposition
rate of the cermet film. 相似文献
3.
S. Scalat D. Banu D. Hawes J. Parish F. Haghighata D. Feldman 《Solar Energy Materials & Solar Cells》1996,44(1):49
Full scale thermal storage tests were conducted in a room lined with PCM wallboard having latent heat storage capacity. The results were compared with those obtained from tests conducted in a similar room lined with ordinary wallboard. The research showed that PCM wallboard can function efficiently as a thermal storage medium which can be applied to peak load shifting, improved use of waste and solar heat as well as more efficient operation of heating and cooling equipment. 相似文献
4.
Popa Iolanda V. Burlacu Alexandru Gavrilescu Otilia Dranga Mihaela Prelipcean Cristina Cijevschi Mihai Cătălina 《Neural computing & applications》2021,33(21):14133-14146
Neural Computing and Applications - Colonoscopy is the “gold” standard for evaluating disease activity in ulcerative colitis (UC). An important area of research is finding a... 相似文献
5.
Bethany Kolbaba-Kartchner I. Can Kazan Jeremy H. Mills S. Banu Ozkan 《International journal of molecular sciences》2021,22(6)
The relationship between protein motions (i.e., dynamics) and enzymatic function has begun to be explored in β-lactamases as a way to advance our understanding of these proteins. In a recent study, we analyzed the dynamic profiles of TEM-1 (a ubiquitous class A β-lactamase) and several ancestrally reconstructed homologues. A chief finding of this work was that rigid residues that were allosterically coupled to the active site appeared to have profound effects on enzyme function, even when separated from the active site by many angstroms. In the present work, our aim was to further explore the implications of protein dynamics on β-lactamase function by altering the dynamic profile of TEM-1 using computational protein design methods. The Rosetta software suite was used to mutate amino acids surrounding either rigid residues that are highly coupled to the active site or to flexible residues with no apparent communication with the active site. Experimental characterization of ten designed proteins indicated that alteration of residues surrounding rigid, highly coupled residues, substantially affected both enzymatic activity and stability; in contrast, native-like activities and stabilities were maintained when flexible, uncoupled residues, were targeted. Our results provide additional insight into the structure-function relationship present in the TEM family of β-lactamases. Furthermore, the integration of computational protein design methods with analyses of protein dynamics represents a general approach that could be used to extend our understanding of the relationship between dynamics and function in other enzyme classes. 相似文献
6.
The present study evaluates the impact of blending organosolv and kraft lignins, which are natural polymer by‐products in the pulp and paper industry, with plasticized poly(vinyl chloride) (PVC) in flooring formulations. Also examined is the impact of replacing dioctyl phthalate, a PVC industry general‐purpose plasticizer, with diethylene glycol dibenzoate (Benzoflex 2‐45), tricresyl phosphate (Lindol), or alkyl sulfonic phenyl ester (Mesamoll) in these formulations. The influence of the different types of lignins and plasticizers on the processibility, thermal, and mechanical properties of the blends is discussed. These properties demonstrate that partial replacement of PVC (20 parts) with different lignins is feasible for some formulations that can be successfully used as matrices for a high level of calcium carbonate filler in flooring products. In addition, the data demonstrate that the presence of certain plasticizers, which interfere with the intramolecular interactions existing in lignins, may allow the lignin molecules to have more molecular mobility. The morphology and the properties of PVC plasticized lignin blends are strongly influenced by the degree and mode of the lignin plasticization and its dispersion within the PVC matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2732–2748, 2006 相似文献
7.
In this work, we design a multisensory IoT-based online vitals monitor (hereinafter referred to as the VITALS) to sense four bedside physiological parameters including pulse (heart) rate, body temperature, blood pressure, and peripheral oxygen saturation. Then, the proposed system constantly transfers these signals to the analytics system which aids in enhancing diagnostics at an earlier stage as well as monitoring after recovery. The core hardware of the VITALS includes commercial off-the-shelf sensing devices/medical equipment, a powerful microcontroller, a reliable wireless communication module, and a big data analytics system. It extracts human vital signs in a pre-programmed interval of 30 min and sends them to big data analytics system through the WiFi module for further analysis. We use Apache Kafka (to gather live data streams from connected sensors), Apache Spark (to categorize the patient vitals and notify the medical professionals while identifying abnormalities in physiological parameters), Hadoop Distributed File System (HDFS) (to archive data streams for further analysis and long-term storage), Spark SQL, Hive and Matplotlib (to support caregivers to access/visualize appropriate information from collected data streams and to explore/understand the health status of the individuals). In addition, we develop a mobile application to send statistical graphs to doctors and patients to enable them to monitor health conditions remotely. Our proposed system is implemented on three patients for 7 days to check the effectiveness of sensing, data processing, and data transmission mechanisms. To validate the system accuracy, we compare the data values collected from established sensors with the measured readouts using a commercial healthcare monitor, the Welch Allyn® Spot Check. Our proposed system provides improved care solutions, especially for those whose access to care services is limited. 相似文献
8.
Noraini Nordin Samikannu Kanagesan Nur Rizi Zamberi Swee Keong Yeap Nadiah Abu Subramani Tamilselvan Mansor Hashim Noorjahan Banu Alitheen 《IET nanobiotechnology / IET》2017,11(3):343
In this study, nanocrystalline magnesium zinc ferrite nanoparticles were successfully prepared by a simple sol–gel method using copper nitrate and ferric nitrate as raw materials. The calcined samples were characterised by differential thermal analysis/thermogravimetric analysis, Fourier transform infrared spectroscopy and X‐ray diffraction. Transmission electron microscopy revealed that the average particle size of the calcined sample was in a range of 17–41 nm with an average of 29 nm and has spherical size. A cytotoxicity test was performed on human breast cancer cells (MDA MB‐231) and (MCF‐7) at various concentrations starting from (0 µg/ml) to (800 µg/ml). The sample possessed a mild toxic effect toward MDA MB‐231 and MCF‐7 after being examined with MTT (3‐[4, 5‐dimethylthiazol‐2‐yl]‐2, 5 diphenyltetrazolium bromide) assay for up to 72 h of incubation. Higher reduction of cells viability was observed as the concentration of sample was increased in MDA MB‐231 cell line than in MCF‐7. Therefore, further cytotoxicity tests were performed on MDA MB‐231 cell line.Inspec keywords: sol‐gel processing, nanoparticles, nanofabrication, magnesium compounds, zinc compounds, toxicology, biological organs, cancer, cellular biophysics, nanomedicine, calcination, differential thermal analysis, Fourier transform infrared spectra, X‐ray diffraction, transmission electron microscopy, particle size, organic compoundsOther keywords: sol‐gel method, cytotoxic effects, breast cancer cell line, MDA MB‐231 in vitro, nanocrystalline magnesium zinc ferrite nanoparticles, copper nitrate, ferric nitrate, raw materials, calcined samples, differential thermal analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, average particle size, cytotoxicity testing, human breast cancer cells, mild toxic effect, 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyltetrazolium bromide) assay, cell viability, MCF‐7, MDA MB‐231 cell line, size 17 nm to 41 nm 相似文献
9.
In this paper, a new control scheme, the gain scheduled Particle Swarm Optimization (PSO) based PID, is proposed for a continuous stirred tank reactor (CSTR). CSTR is a highly nonlinear process that exhibits stability in certain regions and instability in some regions. Generally, PID controllers are used in these processes. Tuning of the PID controller is required to guarantee the best performance of the CSTR. The proposed scheme implements the characteristics of the PSO's global optimization to tune the PID's control parameters: kp, ki, kd, to obtain the best control effect by minimizing Integral Square Error online. The PID controller parameters tuned for each region using PSO are gain scheduled using fuzzy control. Fuzzy gain-scheduling is a special form of fuzzy control that uses linguistic rules and fuzzy reasoning to determine the controller parameter transition policy for the dynamic plant subject to large changes in its operating state. Simulation results show the feasibility of using the proposed controller for the control of the dynamic nonlinear CSTR. 相似文献
10.
Minos N. Garofalakis Banu Özden Avi Silberschatz 《The VLDB Journal The International Journal on Very Large Data Bases》1998,7(4):206-225
The Enhanced Pay-Per-View (EPPV) model for providing continuous-media services associates with each continuous-media clip
a display frequency that depends on the clip's popularity. The aim is to increase the number of clients that can be serviced
concurrently beyond the capacity limitations of available resources, while guaranteeing a constraint on the response time.
This is achieved by sharing periodic continuous-media streams among multiple clients. The EPPV model offers a number of advantages
over other data-sharing schemes (e.g., batching), which make it more attractive to large-scale service providers. In this
paper, we provide a comprehensive study of the resource-scheduling problems associated with supporting EPPV for continuous-media
clips with (possibly) different display rates, frequencies, and lengths. Our main objective is to maximize the amount of disk
bandwidth that is effectively scheduled under the given data layout and storage constraints. Our formulation gives rise to
-hard combinatorial optimization problems that fall within the realm of hard real-time scheduling theory. Given the intractability
of the problems, we propose novel heuristic solutions with polynomial-time complexity. We also present preliminary experimental
results for the average case behavior of the proposed scheduling schemes and examine how they compare to each other under
different workloads. A major contribution of our work is the introduction of a robust scheduling framework that, we believe,
can provide solutions for a variety of realistic EPPV resource-scheduling scenarios, as well as any scheduling problem involving
regular, periodic use of a shared resource. Based on this framework, we propose various interesting research directions for
extending the results presented in this paper.
Received June 9, 1998 / Accepted October 13, 1998 相似文献